Locating fixture



April 24, 1945- c. D. HARGADON.

LOCATING FIXTURE Filed Dec. 2, 1942 INVENTOR CHARLES D. I-IARGADON finswfm ATTORNEY Patented Apr. 24, 1945 OFF-ICE LOCATING FIXTURE Charles D. Hargadon, St. Matthews, near Louisville, Ky.

Application December 2, 1942, Serial No. 467,671

Claims.

This invention relates to a'special machine tool device which I designed as a locating fixture for locating and/or retaining objects of manufacture in position upon the work face'or table of a machine while being operated upon by the cutting tool thereof.

One of the objects of the invention is to provide a locating fixture, complete as a unit, havingall of the elements and instrumentalities for attachment to a machine tool without requiring the use of auxiliary, external or cooperating tools or objects beyond the use of human hands.

' Another object of the invention is to provide attaching means that will permit the instantaneous attachment or detachment of my locating fixture.

A further object is to provide a locating fixture having a bar equipped with securing means of the simplest design for utility and economical manufacture.

These and further objects will be apparent from the following description when considered in connection with the accompanying drawing in which a preferred embodiment of the invention is illustrated.

Referring to the drawing,

Figure l is a plan view of a fragment of the table of a drill press equipped with my locating fixture embodying the invention disclosed herein.

Figure 2 is a front elevation of Figure 1.

Figure 3 is an end elevation of a fragment of Figure 1 and a vertical section along line 3, 3 of Figure 2.

Figure 4 is a detail in perspective on an enlarged scale of the hooked jaw or gripper for attachment to the vertical depending flange of the table top shown in Figures 2 and 3. a

For the purpose of illustration, my improved locating fixture is shown in simple form and mounted in operating relation on and attached to the end area of the top of a rectangular drill press table designated by the numeral 5.

A locating bar 6 of true section such as extruded or machined right angular steel for-m constitutes the main member. Since each end thereof is equipped with duplicate overthrow apparatus, the description of one of same is understood to apply to both. Each end of bar 6 is formed with a longitudinal slot 1 for receiving a vertically disposed bolt 8 provided with threads at one end for receiving adjustable stop nut 9 and an eye H1 at the other end for engagement with the overthrow operating and locking means. The word overthrow is employed to designate a toggle or over center action for applying longitudinal force to the bolts for securing the bar to the drill press table.

Eye ll! provides a bearing for cross bearing pin or shaft H, which is anchored in holes 12 positioned adjacent the inner ends of arms 83 that project from handle M of a lever, designated generally as L. The upper end of this particular lever- L has been bifurcated to form a yoke. Adjacent each outer end of arms I3 is a bearing I 5 for pin it, the latter being anchored in arms 18 of jaw member, shown in individually in Figure 4 and designated generally as G in Figure 2.

Jaw G is preferably integrally formed with arms l8 projecting from base IS in the formoi a yoke. This yoke is mounted on bearing pins 16 so that the overthrow lever L can be freely oscillated over or through the vertical center line 3, 3 of Figure 2.

To apply my locating fixture to a given table top, nuts 9 are employed to adjust bolts 8 to the proper length in order that the jaws can grip the depending flange 5A of top 5 when levers L are operated inwardly for clamping or securing bar 6 to top'5 in operating or locked relation thereto. When both levers are rotated outwardly through said center line, the bar will be released from the table. Thus, it will be perceived that the bar can be placed at any desired location and instantaneously secured for the uses designated herein. It should be noted that a spring 9A, or other elastic member such as rubber, may be employed between the nuts and top face of bar 6 to provide a cushioning effect and to yieldingly rather than positively secure the bar to the table.

Obviously, elastic member 9A assists the off-center operation and also compensates for minor variations in the cooperating members.

To provide additional facilities for expeditiously locating objects on a table in succession when the same machining operation on each object is contemplated, an adjustable stop or head indicated generally by S, is provided to cooperate with bar 5.

In Figures 1, 2 and 3 rectangular blocks B has been employed to represent an object located by the incident instrumentalities.

A series of equidistant transverse holes 6A in bar 6 receive screw IT. This screw cooperates with a threaded hole in head S for securing the same at a selected location. Locating screw HA extends through one of the threaded holes in head S, the one in which screw HA is lodged, or hole 22, to provide a stop for objects to be located and operated upon. Thus, after the locating apparatus has been set as explained,

each block or other object to be operated upon can be located and drilled with drill D, with substantially the same speed and accuracy as though a special drilling jig orfixture had been provided. Obviously, the locating apparatus can be attached to a machine tool and adjusted for a given operation, reset for another operation or removed from the machine tool with a minimum expenditure of time; thus, accomplishing the objects of this invention adverted to at the outset of this specification.

It will be understood that I desire to comprehend within my invention such modification as may be clearly embraced within the scope of my claims and invention.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A locating fixture for attachment to a table top comprising a main bar having a vertical face against which an object can be located; a bolt depending from each end of said bar; a tensioning member disposed between said bolt and said bar; each of said bolts having an operating lever pivoted thereto; a clamping jaw pivoted to said lever and adapted for securing and releasing said bar from said table, said tensioning member so arranged as to exert tension upon the operating lever to hold it in an overthrown position and hold the jaw in securing position.

2. In a locating fixture adapted for attachment to a table top of a machine tool; said fixture comprising a main bar provided with a face for engagement with the top of said table and a vertical fiat face against which an object can be located, and apparatus operatively associated with each end of said bar for securing and releasing the bar from the top surface of said table, each of said apparatuses comprising a jaw clamp for engagement with said top and an overthrow lever articulated to a member depending from one of said ends on a given axis and articulated to said clamp on another axis and adapted to operate said clamp to secure and release the bar from said table.

3. In a locating fixture adapted for attachment to a flanged table top of a machine tool; said fixture comprising a main bar provided with a face for engagement with the top face of said table and a vertical flat face against which an object contacting said top face can be located, and apparatus operatively associated with each end of said bar and said flange for securing and releasing the bar from the table top, said apparatus comprising a clamp for engagement with said flange and an overthrow lever adapted to operate said clamp for securing to and releasing the bar from said table.

4. A locating fixture for attachment to the top of a table for locating objects thereon comprising in combination a main bar having an adjustable stop cooperating with a vertical face thereof against which an object to be located can rest while resting on said top for receiving a machining operation; and a bolt depending from each end of said bar, each of said bolts having an overthrow lever pivoted to the lower end thereof and each of said levers having a jaw clamping means pivoted thereto for securing to and releasing said bar from said top.

5. In a locating fixture adapted for attachment to a table top of a machine tool; said fixture comprising a main bar provided with a face for engagement with the top face of said table and stop members against which an object contacting said top face can be located, and apparatus operatively associated with each end of said bar for securing and releasing the bar from the table top, said apparatus comprising an operating lever pivoted to a member depending from said bar and a jaw clamp pivoted to said lever for engagement with said top, said operating lever adapted to operate said jaw clamp for securing the bar to said table top, and tensioning means so arranged as-to exert tension upon said operating lever so as to hold the jaw clamp and bar in clamped position.

CHARLES D. HARGADON. 

